DETROIT – Jason Giambi didn’t lie about how tough yesterday afternoon was going to be for him. Giambi was benched for the Yankees’ Game 4 of the AL Division Series after going 1-for-8 with two RBIs in the first three games against the Tigers.

“It’ll be miserable, but I’m not going to let it take away from my teammates,” he said. “The more important thing is it’s not about me, it’s about winning games.”

Giambi received a cortisone shot in his right shoulder after Friday’s game, but both he and Joe Torre said that wasn’t the reason he was benched. The news trickled out from a group interview, conducted by Yankees legend Reggie Jackson during batting practice.

“I wanted to make sure I wasn’t sore after not playing first base for a while,” Giambi said. “It’s an elimination game. I wanted to be available to play.

“I’m 100 percent. I can play first or do whatever they need.”

Added Torre: “This had nothing to do with him not playing. If we were to find a health issue, it was not the shoulder.”

Giambi also is playing with a torn left wrist ligament, although he insisted he was “fine.”

Despite being hitless in his past 10 plate appearances, he said, “I’m doing great,” when asked about his swing.

Giambi was given the news personally by Torre, who mentioned the need to get Melky Cabrera into the lineup. As the lefty slugger relayed the conversation, he sounded more like a disappointed Little Leaguer than one of the most potent hitters in the majors.

“He just wanted to give Melky a chance to play out there,” Giambi said.

Torre mildly scolded a Post reporter who began a pregame press conference with a question about Alex Rodriguez batting eighth.

“You found that A-Rod hitting eighth is more important than Giambi not playing. See, that’s not fair,” Torre said. “That’s not fair.